The Superiority of the Laryngeal Mask Airway to the Pentax(R)AirwayScope Used by an Unskilled Pre-hospital Rescuer: A Randomized, Controlled, Crossover Mannequin Study

INTRODUCTION: Recent studies have highlighted the use of a video laryngoscope, a promising airway device that enables faster intubation than a Macintosh laryngoscope without the cessation of chest compressions. The aim of this study was to compare the performance of a Pentax AirwayScope (AWS) with that of a laryngeal mask airway (LMA) when utilized by unskilled personnel in a mannequin model while performing chest compressions. METHODS: We conducted a randomized controlled crossover trial to compare the effects of these two airway devices. A total of 36 participants performed intubation on a mannequin, with each device in both common and moderate level of difficulty airway scenarios. The time to successful ventilation, rate of ventilation success, and subjective difficulty in manipulating the devices were compared. RESULTS: In a scenario with airways of common difficulty, the LMA had a shorter time interval to successful ventilation than the AWS (13.6 vs. 25.2 seconds, respectively, p<0.001). In a scenario with moderately difficult airways, the LMA was also shorter than the AWS (14.5 vs. 26.9 seconds, respectively, p<0.001). For every level of difficulty for the airway, the LMA showed a higher successful ventilation rate and a lower extent of difficulty in device operation than the AWS (p<0.05). CONCLUSION: In the pre-hospital setting, using the LMA could enable an unskilled rescuer to establish airway patency more rapidly. LMA might also be safer and easier for operation than the AWS.

A Comparison of Compression Rates on the Quality of Cardiopulmonary Resuscitation

PURPOSE: In cardiopulmonary resuscitation (CPR) there are different opinions on the compression rate that should be applied. The aim of this study was to compare the total number of adequate compressions delivered during a five-minute period among four groups of lay persons (> or =139 min-1, 129-138, 114-128, and 100 times/minute and a depth of >5 cm for five minutes. A total of 86 participants were then divided into four groups based on their mean compression rate. Age, sex, and body mass index were analyzed as factors affecting the compression rates. RESULTS: The group delivering a compression rate above 139 compressions min-1 performed better than those delivering below 114 compressions min-1 (p=0.03). There was no significant difference in the mean compression depth (p=0.13), percentage of incomplete chest recoil (p=0.277), or the percentage of incorrect hand positioning (p=0.091). All participants (except five) performed chest compressions at a rate above 100 compressions min-1. CONCLUSION: Our results suggest that a chest compression rate above 139 compressions min-1 does not deteriorate the quality of compressions compared to a lower chest compression rate (below 114 min-1) during a five-minute period. Most untrained lay people performed chest compressions well, within a range of 100~150 min-1.